Polychlorinated biphenyls (PCBs) in Drinking Water: Complete Guide (2026)

What is Polychlorinated biphenyls (PCBs) and Why Does It Matter?

# Polychlorinated Biphenyls (PCBs) in Drinking Water: What You Need to Know

PCBs are industrial chemicals that were widely manufactured from the 1930s through the 1970s. They don't break down easily in the environment, which means they persist in water systems decades after their use was banned in the United States. PCBs enter drinking water through contaminated groundwater near old industrial sites, electrical equipment disposal areas, and landfills. Once in the water supply, these chemicals are difficult to remove without proper filtration. Nine water systems across the country currently exceed the EWG health guideline for PCBs, with levels reaching as high as 0.5 ppb (parts per billion).

The health risks from PCB exposure are serious and well-documented. The EPA classifies PCBs as probable human carcinogens, meaning they can increase cancer risk with long-term exposure. Studies show that PCBs also damage the immune system, making it harder for your body to fight infections. Children are particularly vulnerable because their developing brains are more sensitive to PCBs' effects on learning and behavior. The Environmental Working Group (EWG) set their health guideline at 0.06 ppb based on cancer risk assessments. This means water systems showing 0.086 ppb on average—and up to 0.5 ppb at their highest—exceed what independent health experts consider safe for lifetime consumption.

The EPA's legal limit for PCBs in drinking water is 0.5 ppb. This sounds protective, but it's important to understand what this number means. The EPA's standard is based on preventing cancer in 1 in 10,000 people over a lifetime. The EWG's guideline of 0.06 ppb is stricter because it aims to protect 1 in 1 million people from cancer risk. Nine water systems have tested above the EWG guideline, meaning they exceed what independent scientists recommend for safe drinking water. If your water system is one of them, you shouldn't wait for regulations to change—you can take action now to protect your family.

Florida leads the nation with 10 water systems exceeding the EWG guideline, followed by Kentucky with 4 systems. Ohio, Arizona, and Delaware round out the affected states. Florida's contamination pattern reflects its industrial history and the persistence of PCBs in the state's groundwater. Kentucky and Ohio's manufacturing heritage means older industrial sites continue to leach PCBs into drinking water supplies. These aren't isolated problems—they're concentrated in regions where PCBs were heavily used and improperly disposed of decades ago.

Removing PCBs from drinking water requires advanced filtration. Activated carbon filters are highly effective at capturing PCBs, removing up to 99% of these chemicals from water passing through them. Reverse osmosis systems also work well, blocking PCBs along with other contaminants. If you live in Florida, Kentucky, Ohio, Arizona, or Delaware—or anywhere with industrial contamination concerns—having your water tested for PCBs is a smart first step. A whole-house activated carbon system protects your entire family's water use, while point-of-use filters on your kitchen sink focus protection where you drink and cook. Testing through Echo Water can identify whether PCBs are present in your specific water supply, helping you choose the right filtration solution for your home.

Regulatory Standards for Polychlorinated biphenyls (PCBs)

Cities With the Highest Polychlorinated biphenyls (PCBs) Levels

States Most Affected by Polychlorinated biphenyls (PCBs)

Frequently Asked Questions

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